Communication standards applied to communication systems in recent years include, for example, Division Multiple Access (W-CDMA), Long Term Evolution (LTE), Worldwide Interoperability for Microwave Access (WiMAX: IEEE802.16-2004, IEEE802.16e, etc.). Further, the communication standards may include Orthogonal Frequency Division Multiplexing Access (OFDMA).
Signals transmitted by the communication systems based on above described communication standards are wideband and have a high peak-to-average power ratio (PAPR). Generally, the signals are transmitted after amplifying by a power amplifier (PA). PAPR of the transmitted signals is reduced by clipping of the maximum signal amplitudes at the some predefined level.
For more information, see the U.S. Application Publication No. 2011/0092173 A1 (patent document 1), “J. Armstrong, “New OFDM peak-to-average power reduction scheme,” in Proceedings of IEEE on Vehicular Technology, (IEEE, 2001), pp 756-760” (non-patent document 1), and “Hsin-Hung Chen, et al., “Joint Polynomial and Look-Up-Table Predistortion Power Amplifier Linearization,” IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS-II: EXPRESS BRIEFS, VOL. 53, NO. 8, AUGUST 2006” (non-patent document 2).
However, the signal amplitude clipping introduces a clipping noise into the transmitted signals.